1. Field of the Invention
The present invention relates to a paper feeding mechanism for a printer.
2. Description of the Prior Art
Conventionally, large-sized printers provided with automatically loading mechanism have been used as output devices of word processors or the like. In such an automatically loading mechanism, a paper pressing roller is separated from platen by an operation lever projected outward, and then a push-button is depressed to start a paper feeding motor so that a paper is automatically drawn in. As another example of the paper feeding mechanisms, there have been frictionally paper feeding mechanisms having such a structure that a spring is fixed to a frame of a printer and a pinch roller is held by the spring, or such a structure that a pinch roller is pressed by a spring attached on a bottom plate of a printer.
In such automatically loading mechanisms and frictionally paper feeding mechanisms in the prior art, operations are complicated because both the operations of the operation lever and the push-button are required. Further, when recording paper is inserted as well as fed, the resilient force by which the pinch roller is urged against the platen is always so strong that the recording paper does not facilitate to be inserted between the platen and the pinch roller even if the front end of the recording paper has come into contact with the pinch roller. Thus, it is not easy to set the recording paper. Further, when the recording paper is fed by a pin tractor or the like, it is necessary to separately provide a mechanism for causing a pinch roller to separate from a platen against a spring, resulting in a complicated structure.